Tornado outbreak of July 21, 2019
the 'Tornado outbreak of July 21, 2019 '''was a destructive tornado outbreak which primarily effected the lower Ohio Valley and upper Tennessee Valley during the late morning through early evening hours of July 21, 2019. In total 51 tornadoes touched down during a 8 hour period from 11:36AM through 7:50PM Eastern Time. Meteorological History The 12Z GFS model run on July 15 suggested a major tornado outbreak was going to unfold in the eastern United States at some point in the July 20-23 range. By July 18, model runs had narrowed down the very different model runs from the previous few days down to a tornado outbreak was possibly going to unfold on July 21 in the late morning and early afternoon hours over the lower Ohio and upper Tennessee valleys. Shortly later, the SPC issued a Day 4 30% severe weather outlook for that area. A Day 3 Enhanced Risk was issued early on July 19 with "large hail and destructive winds being likely, but a few strong tornadoes not being out of the question.", on July 20, CAPE levels were believed to have been in the perfect regions for a tornado outbreak in southern Indiana/northern Kentucky. It was also noted that moisture and warm temperatures would create conditions favorable for severe thunderstorm development in the Upper Tennessee and Lower Ohio Valleys, mainly in the 1-4PM EDT timeframe. Wind shear was forecast to be strong enough to produce some tornadoes. In the 1730Z D2 outlook, the SPC upgraded the Enhanced Risk to a Moderate Risk of Severe Thunderstorms with a 15% SIG (Moderate) tornado potential being the main concern. By 8AM the next morning, temperatures across the lower Ohio Valley had stagnated at 70 degrees as rain showers moved through the area. The SPC issued a High Risk of Severe Thunderstorms around that same time for the Evansville-Owensboro area. The first Severe Thunderstorm Warnings were issued in the 9:00-9:45AM time-frame across western KY. A PDS tornado watch was issued at around 10:00AM local time for the Evansville-Owensboro-Louisville area. At 11:29AM, spotters reported a funnel cloud northwest of Morganfield, Kentucky. The NWS in Paduach issued a tornado warning with the storm at 11:31AM, making it the first tornado warning of the day. Meanwhile widespread severe thunderstorm development had already occurred throughout the area, at 11:36AM, a EF0 tornado touched down about 5 miles north of Morganfield and lifted at 11:38AM. At 11:46AM, radar indicated a strong tornadic signature near Texas City, Illinois (which was only under a slight risk). The NWS in Paducah, concerned about a extremely dangerous tornado that could touch down, issued a PDS Tornado Warning for the city of Texas City at 11:50AM. The first violent tornado of the outbreak touched down at 12:01PM, as a EF4 touched down over Texas City, causing intense damage to the city. This low-end EF4 was originally given a preliminary rating of EF5, before being downgraded in Fall 2019. Despite this, no one died in the Texas City tornado. A PDS Flash Flood Watch was issued by the National Weather Service in Indianapolis at 12:17PM, noting that "''Slow moving strong to severe thunderstorms will move through Indiana as a slow moving warm front enters the region in the early afternoon hours. Widespread severe flooding is likely south of Interstate 70 but could occur as far north as southern Madison County. Moderate to low end flooding is expected elsewhere.", storms continued to move east as 3 supercells were noted on doppler radar, including the one which had previously produced the Texas City EF4. These storms were behind a fast moving line of extremely severe thunderstorms. Meanwhile, more slow moving thunderstorms were developing southwest of Indianapolis, moving eastward towards the Cincinnati-Louisville area. Another supercell developed near Owensboro at around 1:11PM, and quickly produced a EF1 tornado which flipped a mobile home, killing 1 person. The NWS in Paducah had upgraded the previously in effect Severe Thunderstorm Warning for the Owensboro-South Evansville area to a Tornado Warning, noting that a "Fast moving severe thunderstorm capable of producing short-lived tornadoes" was located 14 miles south of Owensboro, and moving north. Another violent tornado would touch down with this storm just 10 minutes after the tornado warning was issued, the tornado quickly intensified into a EF2 as it missed Owensboro, a tornado emergency was declared for Evansville at 1:36PM, with a piece of text noting that a "Large, violent, and fast moving tornado" was approaching East Evansville. It hit Evansville at 1:42PM as a EF4 tornado before weakening as it moved northeast. By 3:00PM, after 26 tornadoes had touched down across Kentucky, southeastern Illinois and southern Indiana, the storms in that area had gusted out, however...slow moving violent thunderstorms were developing in the Enhanced Risk area including central Indiana (which was upgraded to a Moderate Risk in the 4PM outlook). The third and final violent tornado of the day touched down at 5:01PM near Zionsville embedded within a slow-moving thunderstorm complex, the EF4 tornado caused moderate damage to Lapel, Indiana and caused severe damage to Anderson before weakening and lifting at 5:48PM. The storms continued and the final tornado lifted at 7:40PM in western Ohio. In total 7 people died, one in the Owensboro EF1, 5 in the Evansville EF4 and 1 in the Anderson EF4. The storms had mostly diminished by 9PM local time. Public Severe Weather Outlook (11:27AM) PUBLIC SEVERE WEATHER OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1027 AM CDT SUN JUL 21 2019 ...Outbreak of severe thunderstorms and possibly tornadoes expected over the lower Midwest and Ohio River Valley late this morning through early tonight... * LOCATIONS... Northeastern Missouri Northwestern Tennessee Western Kentucky Southeastern Missouri Southern and central Indiana * HAZARDS... Several tornadoes, a few intense and long-track. Scattered damaging winds, some hurricane force. Widespread large hail, some up to golf ball size. * SUMMARY... Discrete supercells are forecast to develop in southern Illinois late this morning, and move northeast with a upper-level trough. This could lead to a outbreak of tornadoes and violent severe thunderstorms across the discussion area. A few long-track, destructive and potentially violent tornadoes are possible, especially along the Ohio River. More isolated severe thunderstorms can be anticipated elsewhere across the Midwest today. Preparedness actions... Review your severe weather safety procedures for the possibility of dangerous weather today. Stay tuned to NOAA Weather Radio, weather.gov, or other media for watches and warnings. A tornado watch means that conditions are favorable for tornadoes to form during the next several hours. If a tornado warning is issued for your area, move to a place of safety, ideally in a basement or interior room on the lowest floor of a sturdy building. && ..Edwards.. 07/21/2019 $$ Notable tornadoes Texas City, Illinois A fast moving severe and tornadic thunderstorm produced a tornado at 12:01PM local time near Texas City, Illinois...the tornado rapidly intensified into a EF4 wedge tornado as it moved over Texas City, causing extreme damage to houses. Despite this, no one died in this tornado (which occurred within the Slight Risk area). The tornado lifted at 12:32PM local time after causing about $14.63 million in damages. Owensboro, Kentucky About a hour after the Texas City EF4 wedge, a EF1 cone tornado touched down near Owensboro in Kentucky, causing light to moderate damage to houses. But did cause a single death when a mobile home flipped over. However, the tornado was rated a EF1 as it fell less than a mile per hour short of EF2 status, with many sources rating it as a EF2, as it was as close as you could get. Evansville, Indiana See article here: 2019 Evansville tornado Shortly after the Owensboro tornado lifted, another tornado with the same cell touched down, this one being the strongest and deadliest of the outbreak. The tornado quickly moved north over the Ohio River and into southern Indiana, before it moved into the Evansville area, causing mass devastation and producing nearly $400 million in damages. 4 people died in this tornado. The tornado diminished at 2:11PM however, after almost a hour on the ground. Zionsville-Chesterfield, Indiana As a slow moving complex of severe thunderstorms continued to move eastward, the third and final EF4 of the outbreak touched down at 5:01PM, it caused moderate house damage in Zionsville and much of Anderson, however it did cause isolated EF4 damage in Anderson. The tornado lifted at 5:48PM near Daleville. Non-tornadic impacts Texarkana, Texas derecho A large bow echo effected portions of northeastern Texas, southern Arkansas, southeastern Oklahoma, northern Louisiana and even into Mississippi shortly after sunset on July 21. This event produced 2 separate tornadoes, often considered not part of the outbreak, a EF2 over rural southern Arkansas, and a EF0 over northern Mississippi, near Holly Springs. A maximum wind gust of 100 mph was recorded near the Texas-Oklahoma state line, and 2 people were killed in Texarkana, which almost completely lost power. This derecho was unexpected, with the area only being under a slight risk of severe thunderstorms, and no severe thunderstorm or tornado watch was in effect at the time of the bow echo's formation. However, Severe Thunderstorm Watch #516 was issued as the system got itself together. Mackinaw City, Michigan derecho Another large bow echo originated over northern Wisconsin, in what was, at the time, a slight risk area. Tornado Watches #508 and #509 both had a high damaging wind potential, with a moderate tornado and low damaging tornado potential. Tornado Watch #509 stated the possibility for scattered wind gusts nearing 100 mph, one of the few watches of it's kind on record. Widespread damaging winds of 60-80 mph were recorded across northeastern Wisconsin and far southern upper Michigan, with a maximum wind gust of 106 mph occurring at Green Bay, Wisconsin. The storm continued to produce winds of nearly 90-100 mph over Lake Michigan and as it impacted Mackinaw Island and City, warranting a moderate risk issuance for the area. Heavy to extreme mobile home damage was noted in Mackinaw City, with nearly 120 trees being uprooted as well, the entire city lost power. A maximum wind gust of 102 mph was recorded in Mackinaw City. The squall line also produced 2 EF3 tornadoes. South Bend, Indiana-Bowling Green, Kentucky squall line A absolutely massive squall line emerged out of the previously discrete supercells that afternoon, producing widespread wind gusts of 70-80 mph, with some wind gusts approaching 105 mph in spots, impacted almost all of Indiana and Kentucky that afternoon. This squall line produced the Zionsville-Chesterfield, Indiana EF4, as well as the Muncie, Indiana EF2. This squall line also produced a EF3 near South Bend, and widespread wind damage resulted in the high risk shifting towards primarily a damaging wind threat in the 20Z and 01Z outlooks. A maximum wind gust of 109 mph was recorded at Lafayette, Indiana, in the moderate risk area. Ohio-White River floods of July-September 2019 Significant river flooding also was recorded in Indiana, with the White River overflowing its banks at Anderson, and the Ohio River warranting widespread flash flood emergencies across it's area. Nearly 10 flash flood emergencies were in effect by midnight on July 22, and 39 flash flood warnings were in effect. River flooding would continue into early September thanks to another severe weather event and a unusually wet August.